The kanji here are different colors (gold and silver) and the kanji themselves have some variations. The one to the left appears to be post-WW2, while the other is pre-WW2.

Latch differences

Hook latch

No latch (probably post-WW2)

Button latch

Note another subtle difference: the rounded corners on the earlier case; the sharp ones on the later case.

Hinge differences: the bottom hinge is on the earlier case (with the hook latch); the top hinge is on the later case (with no latch). The top hinge appears to be spring-loaded.

8th Class Rising Sun. Gold kanji in two rows. Meiji-era?

8th Class Sacred Treasure.Gold kanji in classical style.

Order Presentation Cases

The orders and some medals had lacquered wood presentation cases. There is a great variety of cases even those made for the same medal. The inscription may be one or two rows, it may be in gold or silver, and there may be variations in the kanji strokes.

The cases may have a push-button latch, a hook latch, or no latch at all. Some cases are thick; some are thin. Some have protruding hinges; some have hidden hinges.

Supposedly one can determine the period of the case by noting these differences, but I can find no resource where this information is available. Peterson mentions nothing about this issue in his book.

I hope to study more Japanese sources and note anything about the cases here. Does anyone have any information, either second-hand or source material? I will list ideas as they are presented.

Very early 8th Class Rising Sun case. Most likely one of the first cases made. Note that the shape is almost a square and that the latch is on the inside lid rim.